针对纳米定位平台的自适应IIR带阻滤波器设计

Design of Adaptive IIR Band-Stop Filter on Nano Positioning Stage

针对纳米定位平台本身机械结构以及负载发生变化时,其固有频率变化造成谐振频率也随之改变的问题,提出了一种自适应IIR带阻滤波器来滤除谐振噪声。通过对纳米定位平台阶跃响应频谱图的分析,得到所需参数,即可根据谐振频率的变化自适应地确定滤波器的设计指标。在下位机FPGA实现中,运用移位相加算法代替了乘法器的功能,节省了硬件资源,优化了系统结构,减小了总体运算量。通过仿真表明,自适应IIR带阻滤波器可有效滤除纳米定位平台的谐振噪声,具有良好的实用性。

The natural frequency changes of mechanical structure and load on nano positioning stage cause the change of resonance frequency.The adaptive IIR band-stop filter is designed for filtering resonance noises to solve this problem.The necessary parameters of filter are gotten by analyzing the spectrum of step response on nano positioning stage.Design index of filter could be adaptively changed with variety of resonance frequency.In the realization based on FPGA,shifting and adding operations are used to realize multiplier functions.